Clock casing



FIG. 1 is a front isometric view of a clock casing showing our new design;

FIG. 2 is a front elevational view thereof the rear being a mirror image thereto;

FIG. 3 is a side elevational view thereof, the opposite side being a mirror image thereto;

FIG. 4 is a top plan view thereof,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a clock casing, as shown and described. 